Assessment of stability analysis methods presented in AISC design codes for braced frames /

Saçılık, Yılmaz Erdinç
Stability is one of the main issue for the steel frame design. Besides, it would be very complex to deal with especially multi bays, multi storey real structures. Prior to the AISC 2005, stability analysis was generally conducted with Effective Length Method, although it has several inapplicability and limitations. However, together with the AISC 2005, a new stability analysis design approach, Direct Analysis Method, was taken the place of the specification. The aim of this study was to assess Stability Analysis Methods defined in different American specifications, AISC ASD 1989, AISC LRFD 1999, AISC 360-05 and AISC 360-10. These stability analysis methods were researched according to the Specifications as well as in available technical literature, and then were evaluated by their usage and limitations. To achieve this aim, five analytical models were investigated using the Effective Length Method and the Direct Analysis Method according to Allowable Strees Design (ASD) and Load and Resistance Factor Design (LRFD). The first model was a one bay, one story portal frame with X brace, second model was also a one bay, one story portal frame with K brace, third model was a three bay, one story portal frames with interior bay X brace, fourth model was a two vi bay, two story portal frames with X braces and fifth model was a one bay, one story portal frame without any brace. Additionally, to illustrate the effect of column orientation on stability methods, some columns were oriented by their weak axis bending. Finally, an incremental increase and decrease of load values were applied to the first model to examine the effect of loads.


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Citation Formats
Y. E. Saçılık, “Assessment of stability analysis methods presented in AISC design codes for braced frames /,” M.S. - Master of Science, Middle East Technical University, 2014.